Foods to Avoid in Your Diet

Are there foods you never should eat? Not really. If you crave an ice cream sundae occasionally, have a small one. But don’t make it a daily event. If you eat chips at your neighbor’s backyard party, choose healthier snacks at home. Healthy eating is not like many of the popular weight-loss plans that require you to eliminate certain foods entirely. But there are some foods you should eat only rarely.

Harvard nutrition scientists have compiled the following list of foods to keep to a minimum because research strongly shows that consuming these foods regularly — more than other foods — can promote life-threatening illnesses such as heart disease, hypertension, diabetes, and even cancer (see “The food-health connection”).



Added sugar

Whether it’s white granulated sugar, brown sugar, high-fructose corn syrup, corn sugar, or honey, sugar contains almost no nutrients other than the sugar itself, pure carbohydrate. Sugar isn’t dangerous per se, but a heavy sugar intake increases your diet’s glycemic load, fills you up with empty calories, and keeps you from eating healthy foods that contain vitamins, minerals, fiber, and other nutrients. Want evidence? Give a child a sugary drink right before dinner, and most of the meal will stay on the plate. Cutting back on candy, soda, and other sweets is just half the battle, however. There’s lots of hidden sugar in prepared foods, including fat-free snacks and cereal bars. Look for sugar in surprising places such as peanut butter, ketchup, and spaghetti sauce. Even prepared frozen entrées have added sugars. What’s more, snacks that contain good ingredients such as whole wheat, canola oil, and olive oil are no longer as healthy once they’re loaded with sugar.

Here’s your chance to make a big difference in your calorie intake, your weight, and your health. Ask yourself: is this food naturally sweet, or did someone add sugar or honey to make it sweet? Try not to add sugar or honey to tea, coffee, or cereal. Read the labels on packaged foods, and steer clear of foods that have sugar, honey, corn syrup, corn sugar, fructose, or high-fructose corn syrup among the first three ingredients. Other sugar aliases to watch for include agave nectar, brown sugar, cane sugar, corn sweetener, dextrose, maltose, fruit juice concentrate, and glucose.

Despite what you may have heard or read, high-fructose corn syrup, which is widely used in many products, doesn’t seem to be any better or worse for you than any other kind of added sugar. This sweetener has developed such a negative reputation that the Corn Refiners Association has petitioned the FDA to allow a name change to “corn sugar” on ingredients lists. There’s a slight difference between various types of sugar. Table sugar, generally produced from cane plants or beets, is made of one glucose molecule joined to one fructose molecule, so it contains glucose and fructose in equal proportions. High-fructose corn syrup, or corn sugar, also contains glucose mixed with fructose, with just slightly more fructose than glucose. Since table sugar and high-fructose corn syrup are made up of glucose and fructose in roughly similar proportions, it’s likely that both forms of sugar have a similar physiological impact on blood sugar, insulin, and metabolism.

Fast fact

Food manufacturers often make sure sugar doesn’t appear first on the ingredients list by using two or more types of sugar, listed separately; thus, when the ingredients are ranked in order of weight, other ingredients appear first. Avoid foods with several different forms of sugar listed.


Dairy fat

Ice cream, whole milk, and cheese contain a lot of saturated fat and some naturally occurring trans fat and therefore can increase the risk of the health problems traced to bad fats, notably heart disease. The healthiest milk and milk products are low-fat versions, such as skim milk, milk with 1% fat, and reduced-fat cheeses.


Baked sweets

Cookies, snack cakes, doughnuts, pastries, and many other treats are hard to pass up, but they are the very definition of the modern food crisis because the commercially prepared versions are packed with processed carbohydrates, added sugar, unhealthy fats, and often salt.

Doughnuts, for example, are cakes fried in fat and have large amounts of saturated fat, sugar, and calories. But doughnuts present additional problems. For one thing, they’re often eaten for breakfast, replacing what could be a nutritious meal. Second, because doughnuts are often purchased by the dozen, you may be tempted to eat two or more in one sitting. If you’re a doughnut lover, you can improve your diet by eating doughnuts only for dessert, limiting yourself to just one, and making them only an occasional treat. A single doughnut has around 250 calories with 40% from fat — mostly saturated fat.

Other pastries, cookies, pie, croissants, tarts, cake, and Danish have similar issues. Pastries are, by definition, baked goods made with high-fat dough and lots of added sugar. As any chef will tell you, it’s the butter or lard (both saturated fats) or shortening (trans fat) that’s the key to making flaky crusts. And many pastries are topped or filled with buttercream, whipped cream, or icing — each packing a wallop of saturated fat and trans fat (especially in store-bought goods), sugar, and calories. A slice of cheesecake can have 800 calories or more — a large share of the 2,000 to 2,500 you need in a day. Instead, go for the fruit plate or even biscotti, Italian almond cookies made without butter or oil.


White carbohydrates

Whether it’s bread, pasta, potatoes, rice, cookies, cake, or pancakes, it’s best to look for the whole-grain version. Yes, you can find or make whole-grain pancake mix. Whole-wheat pastas and breads are luckily easy to find. And you can always make your own homemade cookies or bars using grains such as oatmeal, and less sugar and unhealthy fats.

Other foods that come in whole-grain versions are muffins, croissants, crackers, bagels, and other baked goods made with white flour. Unless you choose the whole-grain versions, count these among the bad carbohydrates because of their fairly high glycemic load and very little fiber.


Processed and high-fat meats

Shun the cold cuts and “pigs in a blanket” when snacking. Head instead for the vegetable plate. Despite some conflicting reports, the balance of the evidence confirms that processed meats like bacon, ham, pepperoni, hot dogs, and many lunch meats are less healthy than protein from fish, skinless chicken, nuts, beans, soy, and whole grains. Fresh red meat should be eaten sparingly and the leanest cuts selected (see “Choosing meat and fish”). Also, meat is healthier when cooked in ways that don’t char the meat, such as baking or stewing. As noted earlier, browning meat by searing it on the grill or stovetop or under the broiler creates carcinogens. In addition to heterocyclic amines, carcinogens called polycyclic aromatic hydrocarbons (PAHs) can also form when fat and juices from meat drip down to the heat source of the grill, resulting in smoke. The smoke contains PAHs. As the smoke rises up past the food, the PAH compounds can be deposited on the surface of the meat.


Sugary beverages

Research at the Harvard School of Public Health and elsewhere has tied sugary drinks to the obesity epidemic in the United States. Currently, about two-thirds of Americans are overweight or obese. Obesity raises the risk of type 2 diabetes, heart disease, arthritis, and certain cancers. Research cites soft drinks and other sugar-sweetened beverages as the primary source of added sugar in the American diet and a major contributor to weight gain. In fact, downing just one extra 12-ounce can of a typical sweetened beverage daily can add on 15 pounds in a year. That’s not only because the drinks themselves add calories, but also because those liquid calories aren’t as satiating as solid food. According to the American Heart Association, drinking a sugar-sweetened beverage makes you consume more calories in general. And the more you drink, the more you eat. In one study, when the size of a regular soda increased from 12 to 18 ounces, men and women ate 26% and 10% more calories from food, respectively.

A study also linked sugary drinks to an increased risk of heart disease in adults. In addition to raising blood glucose, insulin, and triglycerides, sugar reduces the “good” HDL cholesterol in the blood. Consistent with this effect, the study showed that it wasn’t just weight gain but sugar itself that raised heart disease risk.




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